How is the rest of Idaho under a layer of water, but Salmon Dam seems to be low?

Seriously - most water related videos we have seen over the last few weeks show water levels so high that the water is flowing over spillways and into glory holes. But in this second video you can see that the water level is below previous water levels on the dam. From the beginning of the video there are two distinct lines on the inside of the dam, which is usually an indicator of previous water levels.

How is this area not also flooded? It even seems that there isn't much water in the river in the canyon. The poster, Carl Roessler, just put the videos up a week ago so I assume this is a current video. Have you been out there recently to see if this is where the water level are right now at Salmon Dam?